Surface area to volume ratio effect on diffusion

Following the calculations the students lower the shapes into a cup of ammonia water.

Surface area to volume ratio effect on diffusion

The data gathered this experiment shows that there is a direct relationship between surface area to volume ratio and the time it takes for the agar cube containing phenolphthalein to turn pink in the sodium hydroxide NaOH solution.

A larger surface area to volume ratio results in a shorter time before the agar cube turns pink, while a smaller surface area to volume ratio results in a longer time before the agar cube turns pink.

This is clearly seen in the graph where surface area to volume ratio is plotted against the average reaction time. The points show a downward trend, as indicated by the downward sloping line of best fit.

This shows that there is a negative correlation with reaction rate and surface area to volume ratio. Larger agar cube sizes also result in lower surface area to volume ratios, as when size increases, the surface area increases by a lower factor when compared against the increase in volume, thus reducing surface area to volume ratio.

Therefore, the size of the agar cube also has a direct positive correlation with the time it takes for the agar cube to turn pink. The correlation coefficient was also calculated in order to verify the relationship between surface area to volume ratio and the reaction time.

The correlation coefficient was found to be Correlation, however, does not imply causation. While there the data supports a strong negative correlation between surface area to volume ratio and average reaction time, it alone does not imply causation. What supports the hypothesis that higher surface area to volume ratio causes lower reaction time for the agar cube to turn pink is that the experiment was done in a controlled manner.

Only a single independent variable was being changed size of agar cube, and thus, surface area to volume ratio. Other factors were kept constant throughout the entire experiment. Therefore, what caused the dependent variable to change reaction time for the agar cube to turn pink must have been the surface area to volume ratio.

Surface area to volume ratio effect on diffusion

Thus, the hypothesis that surface area to volume ratio affects the time it takes for the agar cube to turn pink due to diffusion of sodium hydroxide NaOH can be accepted as true. There is a general trend of decreasing reaction time as the surface area to volume ratio increases, showing a negative correlation between surface area to volume ratio and reaction time.

Limitation of experimental design: The standard deviation values for the 2 x 2 x 1 cm and 3 x 3 x 1 cm agar cubes were both calculated to be relatively high at 4. The standard deviation was then included in the graph for surface area to volume ratio and reaction time as error bars, showing how the data collected is not perfectly precise.

The variation in the reaction time measured can come from various sources of systematic and random errors. One systematic error is that the sodium hydroxide solution was constantly reused for the same agar cube size for five trials. The agar cubes containing phenolphthalein reacts with sodium hydroxide molecules, thus decreasing the concentration of sodium hydroxide in the solution after each trial.

Lower concentrations of sodium hydroxide are another factor of the time it takes for the agar cube to turn pink, as higher concentrations lower the reaction time due to the collision theory, which states that as the number of molecules of reactants increases, the higher the chance of a successful collision leading to a reaction.

This can be seen in the general increasing trend of reaction time from trial one to trial five for all agar cube sizes.

The difference is much more noticeable in the larger agar cube sizes as larger agar cubes react with more sodium hydroxide and decrease the concentration of sodium hydroxide more than the smaller agar cubes.

Lab Report = Surface area to volume ratio effect on diffusion | Irena Sionek - schwenkreis.com

This is also evidenced by the higher standard deviation values for the larger agar cube sizes. There is also a random error in the form of the uncertainty in the agar cube sizes when cut.

It is difficult to cut perfectly sized agar cubes; therefore, the actual agar cubes will have varying sizes rather than uniform ones. The actual size and surface area to volume ratio of the agar cube may be different from what it should be. Again, this increases the errors in the experiment and leads to a higher standard deviation.

Another random error is the stopping the reaction time based on color of the agar cube.the blood. The intestine has a finely wrinkled internal surface, increasing the area through which nutrients are absorbed by the body. Smaller single celled organisms need to have a high surface area to volume ratio in order to survive.

This is because they rely on oxygen diffusing into the cell. Feb 28,  · There is a decreasing trend of surface area to volume as the size of the agar cube increases.

The 1 x 1 x 1 agar cube has the highest surface area to volume ratio while the 3 x 3 x 1 agar cube has the lowest surface area to volume ratio. Compare the surface area to volume ratio of the cm block to the 1 cm block. Compare the surface area to volume ratio of the 1 cm block to the 2 cm block.

Surface area to volume ratio effect on diffusion

. The experiment results seen on the graph (trend line) show that the bigger is the surface area to volume ratio, the bigger is the percentage volume of diffusion, so the rate of . In this exercise the student will calculate the effect that surface area to volume ratio has on the rate of diffusion.

The method is explained and then the student explores how changes in shape affect the SA/V ratio and the rate of diffusion. • To investigate the effect of a change in the surface area to volume ratio on the rate of diffusion.

• Determine how surface area and volume relate to one another Hypothesis If the size of the jelly is large, then the rate of diffusion will be lower.

If the surface area of the cell increases, then the rate of diffusion will decrease.

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